xref: /dpdk/app/test/test_atomic.c (revision fc1f2750a3ec6da919e3c86e59d56f34ec97154b)
1 /*-
2  *   BSD LICENSE
3  *
4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
5  *   All rights reserved.
6  *
7  *   Redistribution and use in source and binary forms, with or without
8  *   modification, are permitted provided that the following conditions
9  *   are met:
10  *
11  *     * Redistributions of source code must retain the above copyright
12  *       notice, this list of conditions and the following disclaimer.
13  *     * Redistributions in binary form must reproduce the above copyright
14  *       notice, this list of conditions and the following disclaimer in
15  *       the documentation and/or other materials provided with the
16  *       distribution.
17  *     * Neither the name of Intel Corporation nor the names of its
18  *       contributors may be used to endorse or promote products derived
19  *       from this software without specific prior written permission.
20  *
21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32  */
33 
34 #include <stdio.h>
35 #include <stdint.h>
36 #include <unistd.h>
37 #include <sys/queue.h>
38 
39 #include <rte_memory.h>
40 #include <rte_memzone.h>
41 #include <rte_per_lcore.h>
42 #include <rte_launch.h>
43 #include <rte_atomic.h>
44 #include <rte_tailq.h>
45 #include <rte_eal.h>
46 #include <rte_per_lcore.h>
47 #include <rte_lcore.h>
48 
49 #include "test.h"
50 
51 /*
52  * Atomic Variables
53  * ================
54  *
55  * - The main test function performs three subtests. The first test
56  *   checks that the usual inc/dec/add/sub functions are working
57  *   correctly:
58  *
59  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to specific
60  *     values.
61  *
62  *   - These variables are incremented and decremented on each core at
63  *     the same time in ``test_atomic_usual()``.
64  *
65  *   - The function checks that once all lcores finish their function,
66  *     the value of the atomic variables are still the same.
67  *
68  * - The second test verifies the behavior of "test and set" functions.
69  *
70  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to zero.
71  *
72  *   - Invoke ``test_atomic_tas()`` on each lcore: before doing anything
73  *     else. The cores are waiting a synchro using ``while
74  *     (rte_atomic32_read(&val) == 0)`` which is triggered by the main test
75  *     function. Then all cores do a
76  *     ``rte_atomicXX_test_and_set()`` at the same time. If it is successful,
77  *     it increments another atomic counter.
78  *
79  *   - The main function checks that the atomic counter was incremented
80  *     twice only (one for 16-bit, one for 32-bit and one for 64-bit values).
81  *
82  * - Test "add/sub and return"
83  *
84  *   - Initialize 16-bit, 32-bit and 64-bit atomic variables to zero.
85  *
86  *   - Invoke ``test_atomic_addsub_return()`` on each lcore. Before doing
87  *     anything else, the cores are waiting a synchro. Each lcore does
88  *     this operation several times::
89  *
90  *       tmp = rte_atomicXX_add_return(&a, 1);
91  *       atomic_add(&count, tmp);
92  *       tmp = rte_atomicXX_sub_return(&a, 1);
93  *       atomic_sub(&count, tmp+1);
94  *
95  *   - At the end of the test, the *count* value must be 0.
96  */
97 
98 #define NUM_ATOMIC_TYPES 3
99 
100 #define N 10000
101 
102 static rte_atomic16_t a16;
103 static rte_atomic32_t a32;
104 static rte_atomic64_t a64;
105 static rte_atomic64_t count;
106 static rte_atomic32_t synchro;
107 
108 static int
109 test_atomic_usual(__attribute__((unused)) void *arg)
110 {
111 	unsigned i;
112 
113 	while (rte_atomic32_read(&synchro) == 0)
114 		;
115 
116 	for (i = 0; i < N; i++)
117 		rte_atomic16_inc(&a16);
118 	for (i = 0; i < N; i++)
119 		rte_atomic16_dec(&a16);
120 	for (i = 0; i < (N / 5); i++)
121 		rte_atomic16_add(&a16, 5);
122 	for (i = 0; i < (N / 5); i++)
123 		rte_atomic16_sub(&a16, 5);
124 
125 	for (i = 0; i < N; i++)
126 		rte_atomic32_inc(&a32);
127 	for (i = 0; i < N; i++)
128 		rte_atomic32_dec(&a32);
129 	for (i = 0; i < (N / 5); i++)
130 		rte_atomic32_add(&a32, 5);
131 	for (i = 0; i < (N / 5); i++)
132 		rte_atomic32_sub(&a32, 5);
133 
134 	for (i = 0; i < N; i++)
135 		rte_atomic64_inc(&a64);
136 	for (i = 0; i < N; i++)
137 		rte_atomic64_dec(&a64);
138 	for (i = 0; i < (N / 5); i++)
139 		rte_atomic64_add(&a64, 5);
140 	for (i = 0; i < (N / 5); i++)
141 		rte_atomic64_sub(&a64, 5);
142 
143 	return 0;
144 }
145 
146 static int
147 test_atomic_tas(__attribute__((unused)) void *arg)
148 {
149 	while (rte_atomic32_read(&synchro) == 0)
150 		;
151 
152 	if (rte_atomic16_test_and_set(&a16))
153 		rte_atomic64_inc(&count);
154 	if (rte_atomic32_test_and_set(&a32))
155 		rte_atomic64_inc(&count);
156 	if (rte_atomic64_test_and_set(&a64))
157 		rte_atomic64_inc(&count);
158 
159 	return 0;
160 }
161 
162 static int
163 test_atomic_addsub_and_return(__attribute__((unused)) void *arg)
164 {
165 	uint32_t tmp16;
166 	uint32_t tmp32;
167 	uint64_t tmp64;
168 	unsigned i;
169 
170 	while (rte_atomic32_read(&synchro) == 0)
171 		;
172 
173 	for (i = 0; i < N; i++) {
174 		tmp16 = rte_atomic16_add_return(&a16, 1);
175 		rte_atomic64_add(&count, tmp16);
176 
177 		tmp16 = rte_atomic16_sub_return(&a16, 1);
178 		rte_atomic64_sub(&count, tmp16+1);
179 
180 		tmp32 = rte_atomic32_add_return(&a32, 1);
181 		rte_atomic64_add(&count, tmp32);
182 
183 		tmp32 = rte_atomic32_sub_return(&a32, 1);
184 		rte_atomic64_sub(&count, tmp32+1);
185 
186 		tmp64 = rte_atomic64_add_return(&a64, 1);
187 		rte_atomic64_add(&count, tmp64);
188 
189 		tmp64 = rte_atomic64_sub_return(&a64, 1);
190 		rte_atomic64_sub(&count, tmp64+1);
191 	}
192 
193 	return 0;
194 }
195 
196 /*
197  * rte_atomic32_inc_and_test() would increase a 32 bits counter by one and then
198  * test if that counter is equal to 0. It would return true if the counter is 0
199  * and false if the counter is not 0. rte_atomic64_inc_and_test() could do the
200  * same thing but for a 64 bits counter.
201  * Here checks that if the 32/64 bits counter is equal to 0 after being atomically
202  * increased by one. If it is, increase the variable of "count" by one which would
203  * be checked as the result later.
204  *
205  */
206 static int
207 test_atomic_inc_and_test(__attribute__((unused)) void *arg)
208 {
209 	while (rte_atomic32_read(&synchro) == 0)
210 		;
211 
212 	if (rte_atomic16_inc_and_test(&a16)) {
213 		rte_atomic64_inc(&count);
214 	}
215 	if (rte_atomic32_inc_and_test(&a32)) {
216 		rte_atomic64_inc(&count);
217 	}
218 	if (rte_atomic64_inc_and_test(&a64)) {
219 		rte_atomic64_inc(&count);
220 	}
221 
222 	return 0;
223 }
224 
225 /*
226  * rte_atomicXX_dec_and_test() should decrease a 32 bits counter by one and then
227  * test if that counter is equal to 0. It should return true if the counter is 0
228  * and false if the counter is not 0.
229  * This test checks if the counter is equal to 0 after being atomically
230  * decreased by one. If it is, increase the value of "count" by one which is to
231  * be checked as the result later.
232  */
233 static int
234 test_atomic_dec_and_test(__attribute__((unused)) void *arg)
235 {
236 	while (rte_atomic32_read(&synchro) == 0)
237 		;
238 
239 	if (rte_atomic16_dec_and_test(&a16))
240 		rte_atomic64_inc(&count);
241 
242 	if (rte_atomic32_dec_and_test(&a32))
243 		rte_atomic64_inc(&count);
244 
245 	if (rte_atomic64_dec_and_test(&a64))
246 		rte_atomic64_inc(&count);
247 
248 	return 0;
249 }
250 
251 static int
252 test_atomic(void)
253 {
254 	rte_atomic16_init(&a16);
255 	rte_atomic32_init(&a32);
256 	rte_atomic64_init(&a64);
257 	rte_atomic64_init(&count);
258 	rte_atomic32_init(&synchro);
259 
260 	rte_atomic16_set(&a16, 1UL << 10);
261 	rte_atomic32_set(&a32, 1UL << 10);
262 	rte_atomic64_set(&a64, 1ULL << 33);
263 
264 	printf("usual inc/dec/add/sub functions\n");
265 
266 	rte_eal_mp_remote_launch(test_atomic_usual, NULL, SKIP_MASTER);
267 	rte_atomic32_set(&synchro, 1);
268 	rte_eal_mp_wait_lcore();
269 	rte_atomic32_set(&synchro, 0);
270 
271 	if (rte_atomic16_read(&a16) != 1UL << 10) {
272 		printf("Atomic16 usual functions failed\n");
273 		return -1;
274 	}
275 
276 	if (rte_atomic32_read(&a32) != 1UL << 10) {
277 		printf("Atomic32 usual functions failed\n");
278 		return -1;
279 	}
280 
281 	if (rte_atomic64_read(&a64) != 1ULL << 33) {
282 		printf("Atomic64 usual functions failed\n");
283 		return -1;
284 	}
285 
286 	printf("test and set\n");
287 
288 	rte_atomic64_set(&a64, 0);
289 	rte_atomic32_set(&a32, 0);
290 	rte_atomic16_set(&a16, 0);
291 	rte_atomic64_set(&count, 0);
292 	rte_eal_mp_remote_launch(test_atomic_tas, NULL, SKIP_MASTER);
293 	rte_atomic32_set(&synchro, 1);
294 	rte_eal_mp_wait_lcore();
295 	rte_atomic32_set(&synchro, 0);
296 
297 	if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
298 		printf("Atomic test and set failed\n");
299 		return -1;
300 	}
301 
302 	printf("add/sub and return\n");
303 
304 	rte_atomic64_set(&a64, 0);
305 	rte_atomic32_set(&a32, 0);
306 	rte_atomic16_set(&a16, 0);
307 	rte_atomic64_set(&count, 0);
308 	rte_eal_mp_remote_launch(test_atomic_addsub_and_return, NULL,
309 				 SKIP_MASTER);
310 	rte_atomic32_set(&synchro, 1);
311 	rte_eal_mp_wait_lcore();
312 	rte_atomic32_set(&synchro, 0);
313 
314 	if (rte_atomic64_read(&count) != 0) {
315 		printf("Atomic add/sub+return failed\n");
316 		return -1;
317 	}
318 
319 	/*
320 	 * Set a64, a32 and a16 with the same value of minus "number of slave
321 	 * lcores", launch all slave lcores to atomically increase by one and
322 	 * test them respectively.
323 	 * Each lcore should have only one chance to increase a64 by one and
324 	 * then check if it is equal to 0, but there should be only one lcore
325 	 * that finds that it is 0. It is similar for a32 and a16.
326 	 * Then a variable of "count", initialized to zero, is increased by
327 	 * one if a64, a32 or a16 is 0 after being increased and tested
328 	 * atomically.
329 	 * We can check if "count" is finally equal to 3 to see if all slave
330 	 * lcores performed "atomic inc and test" right.
331 	 */
332 	printf("inc and test\n");
333 
334 	rte_atomic64_clear(&a64);
335 	rte_atomic32_clear(&a32);
336 	rte_atomic16_clear(&a16);
337 	rte_atomic32_clear(&synchro);
338 	rte_atomic64_clear(&count);
339 
340 	rte_atomic64_set(&a64, (int64_t)(1 - (int64_t)rte_lcore_count()));
341 	rte_atomic32_set(&a32, (int32_t)(1 - (int32_t)rte_lcore_count()));
342 	rte_atomic16_set(&a16, (int16_t)(1 - (int16_t)rte_lcore_count()));
343 	rte_eal_mp_remote_launch(test_atomic_inc_and_test, NULL, SKIP_MASTER);
344 	rte_atomic32_set(&synchro, 1);
345 	rte_eal_mp_wait_lcore();
346 	rte_atomic32_clear(&synchro);
347 
348 	if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
349 		printf("Atomic inc and test failed %d\n", (int)count.cnt);
350 		return -1;
351 	}
352 
353 	/*
354 	 * Same as above, but this time we set the values to "number of slave
355 	 * lcores", and decrement instead of increment.
356 	 */
357 	printf("dec and test\n");
358 
359 	rte_atomic32_clear(&synchro);
360 	rte_atomic64_clear(&count);
361 
362 	rte_atomic64_set(&a64, (int64_t)(rte_lcore_count() - 1));
363 	rte_atomic32_set(&a32, (int32_t)(rte_lcore_count() - 1));
364 	rte_atomic16_set(&a16, (int16_t)(rte_lcore_count() - 1));
365 	rte_eal_mp_remote_launch(test_atomic_dec_and_test, NULL, SKIP_MASTER);
366 	rte_atomic32_set(&synchro, 1);
367 	rte_eal_mp_wait_lcore();
368 	rte_atomic32_clear(&synchro);
369 
370 	if (rte_atomic64_read(&count) != NUM_ATOMIC_TYPES) {
371 		printf("Atomic dec and test failed\n");
372 		return -1;
373 	}
374 
375 	return 0;
376 }
377 
378 static struct test_command atomic_cmd = {
379 	.command = "atomic_autotest",
380 	.callback = test_atomic,
381 };
382 REGISTER_TEST_COMMAND(atomic_cmd);
383